Educational device



June 5 1933. M. RUDOLPH EDUCATIONAL DEVICE Filed Dec. l, 1931 wwwINVENTOR aa/f A! aazp/f Patented June 6, 1933 UNITED STATES LOUIS M.RUDOLPH, OF BROOKLYN, NEW YORK EDUCATIONAL DEVICE Application filedDecember 1, 1931. Serial No. 578,277.

This invention relates to an educational device for children, and moreparticularly to such a device adapted to instruct and aid a child inlearning arithmetic, and at the same time in learning the use of theconventional measurement ruler.

It is of course well known from our own experience that arithmetic,generally speaking, is a puzzle to the ordinary child. Ac- .10cordingly, rit is usually rather diiicult for the average child to graspthe basic fundamentals of this branch of study, such as thekmultiplication table, the principles of division and the like. 1naddition, the tedious hours spent, especially with the multiplicationtable, and the mysteries of division, contain little joy for the averageyoungster and tend to fill his mind with a hatred for arit-hmetic.

I have now constructed a device which greatly facilitates the study ofarithmetic by the child, renders this study a pleasant pastime insteadof a burdensome duty, and at the same time acquaints the child with andgives him an understanding of the use of the conventional measurementruler. The arithmetical device and ruler are cooperatively combined witheach other so that a study of the one necessarily involves a study o ofthe other. Furthermore this combination provides a neat and compactarrangement for carrying and manipulating the arithmetical device. oItis accordingly an object of this invention to construct a combinationruler and an arithmetical device for teaching multiplication anddivision in such a way that a child will be taught the use of the ru erand at the same time' the above branches of aritlnnetic.

Other and further objects of my invention will become apparent from thefollowing description and appended claims.

Referring now to the drawing which discloses an illustrative embodimentof my invention, y

Fig. 1 is a front elevation of a ruler with means for teachingmultiplication and ydivision associated therewith;

Fig. 2 is an enlarged front elevation of one part of the means forteaching arithmetic; and Y Fig. 3 is a section on line 8 3 of Fig. 1.

On the drawing .c y

lhe reference numeral 1 designates a ruler subdivided into inches andfractions of inches in the conventional manner. The ruler disclosed inFig. 1 is shown as having a length of thirteen inches with the propernumerals, designated as 2, beneath each 'inch division. rllhe ruler 1 ispreferably composed of two sections of any suitable material, la and1?), such as metal, wood, cardboard, celluloid or the like, securedtogether at their upper edges 3. If the ruler is made up of a flexiblematerial like cardboard or the like, it can be formed by merely bendinga sheet or strip of this material to provide a pair of sections hingedtogether along the line of the fold. By forming the ruler in this way,the two sections 1a and 1b form a protecting housing for themathematical device described below. It is, however, to be understoodthat the ruler may be formed from a single ply of material. Then made ofcardboard, the cardboard may be impregnated with a substance to make itmore wear resistant.

The mathematical device consists primarily of alplurality of discs 4,such as is shown in Fig. 2, rotatably mounted at their center points 5by means of bearings 5min the housing formed by sections 1a and 1l) ofthe ruler. Each disc 4 is mounted so that its center point is in linewith an inch marking 2 of the ruler, with a portion of one discoverlapping a portion of the adjacent discs.

Each of said discs 4 has two series of numbers loca-ted adjacent theouter edge of the disc, each series occupying about one-half the outersurface of the disc. The first series,in dicated by the referencenumeral 6, which is the same on each disc, runs counter-clockwise andranges from 1 to 12, although it is apparent that the last figure of theseries maybe 5i as high as desired, being limited entirely by vthe sizeof the disc diameter. This series, however, preferably ends at 12, asshown, being similar inthis respect to the usualmultiplication tablesemployed by children. The

second series designated by reference numeral Y 7 runs clockwise andrepresents a range of numbers ruiming from the product of l and thenumber designating the inch marking adjacentto which a particular discis positioned to the product ot twelves times said munber. Obviously,this series, which, as stated, represents the products ot a particularmultiplier and a multiplicand ranging from l to l2, is dilierent on eachdisc.

The outer section la of the ruler l has a slot 8 directly below eachinch marking of the ruler through which may be viewed any number of irstseries 6 on the disc positioned adjacent said marking. Cut out portions8a are also provided in said section la adjacent the lower edge of saidsection and in line with slots 8. Through each cut out portion Se willbe viewed the product of the number representing the inch markingadjacent to which the disc in question is positioned. with a number ofthe lirst series on the disc exposed through a slot S. Fig. l ot thedrawing discloses the numeral 6, ot series 6. exposed through each slot8 and the product oit the muneral 6, with each number design ating aninch marking on the ruler, exposed through the slots Se.

To prevent a` child in operating the discs `trom becoming confused withthe muubcrs on the discs representing products. series '7, and thoserepresenting multiplicands. series 6, it is advisable to make the twoseries oi numbers in different colors, that is, the products may beshown in red and the multiplicands in black. although, oit course, anytwo dissimilar distinguishing colors may be employed.

The operation ot this device is self-explanatory. It a child desires tomultiply any given number up to twelve by a series ot numbers ranging upto twelve, he merely selects a given number designating a certain inchmarking on the ruler and rotates the disc adjacent said marking toexpose the multiplicands in series G, properly colored, successivelythrough a slot 8. The products, series 7, will then automatically beshown through a slot Sa. At the same time, by virtue of the fact thatthe multiplier represents an inch marking of the ruler. the child willbecome cognizant ot the principles of use of the ruler. Furthermore, bysubdividing the ruler into fractions of inches the child, throughrepeated use ot the device. will become to a certain extent familiarwith this branch of arithmetic.

ll/rile I have explained the above device and its operation asapplicable to the teaching ot multiplication, it ot course apparent thatit likewise automatically teaches division. lVhen used for this purposethe numerals representing products, that is. series 7, become dividends,the multipliers, that is. the markings on the ruler designated 2. becomethe divisors, and the multiplicands,

that is, the numbers of series 6, t-he quotients. In other words, theproblems in this case are setup by the numbers exposed through openings8a and the numbers indicating inch markings of the ruler and the resultsare viewed through slots 8.

It is of course to be understood that various modilications of thedevice disclosed above may be made without departing from the spirit ofmy invention. F or instance, it desired, each disc 4 may have two othersets of numbers corresponding to series 6 and 7 on its rear facecooperating with inch markings on rear section lo ot' the ruler, saidmarkings running trom 13 to 25, and slot-s in said rear section similarto slots 8 and Sa for exposing said series ot numbers through saidsection ll).

A further modification might entail the construction ot a ruler ofgreater length than that disclosed in the drawing.

Moreover', it' it is desired to employ as niultiplicainls, numbers, ot ahigher order than l2, another series of numbers similar to series butranging from 13 to thatdesired can be positioned on each disc et belowseries o. A series oi numbers representing the prodiuis oit the numbersof this series with a number representing an inch division ot the rulercould then be inserted on the disc above series 7. Slots would then beprovided above and below slots 8 and Sfr. respectively tor exposing thenumbers of these additional series.

Furthermore, the disc under the inch divi- .sion l could be positionedbeneath the halt or any other traction ot' an inch to teachmultiplication and division with the fraction selected. Or, other discscould be positioned beneath the various half or other inch fractions otthe ruler to acquaint a child with the multiplication and division ofsuch fractions.

In addition, it is not necessary to position the inch markings Q andslots 8 and Sa directly in line, as disclosed in F ig. l. An operativedevice could be provided by positioning the center point of a discbeneath the inch marking preceding or following that, the number ofwhich is to be a multiplier, for the multiplicands on the disc. In sucha case the series of slots 8 and 8ay would be placed in horizontalalignment with the center points of the various discs. Various otherpositionings of the discs with relation to the inch markings and slots 8and Sa could be provided without a material change of' the inventiondisclosed.

It will thus be appreciated that I have provided acombination ruler andarithmetieal device which forms a neat, compact apparatus and in whichthe parts are so coordinated as to give the child, not only a. knowledgeof multiplication and division, but also an understanding of theprinciples of use of a ruler in measuring.

What I desire to claim and secure by Letters Patent is:

1. An educational device comprising a ruler, a plurality of meansmovably mounted thereon, one being positioned adjacent each numberdesignating an inch marking of the ruler, each of said means having twoseries of numbers on the face thereof, any number of one series beingadapted to be read in connection with the number representing an inchmarking adjacent to which a means is positioned to give a mathematicalresult contained in the second series, and means for isolating a numberof the first series, and a number in the second series comprising theresult of the arithmetical use of said first number with the numberrepresenting said inch marking.

2. An educational device comprising a ruler, a plurality of discsrotatably mounted beneath the front face thereof, each disc beingpositioned adjacent a number representing an inch marking on the ruler,each disc l having two series of numbers thereon, any

number of one series being adapted to beV read in conjunction with anumber representing the inch marking adjacent to which a disc is placedto provide a problem in multiplication kor division, the result of whichis given in the other series, said ruler having two series of openingsthrough which are shown the numbers on the disc employed with the numberrepresenting said inch marking and the numbers representing the resultof said problem.

3. An educational device comprising a ruler having a pair of sectionsjoined at their upper edges to provide a housing therebetween, aplurality of discs rotatably mounted in said housing, each disc havingits central point in line with a number representing an inch marking onthe ruler, each disc having two series of numbers thereon, any number ofone series being adapted to be read in conjunction with the numberrepresenting an inch marking adjacent to which a disc is placed toprovide problems in multiplication or division, the results of which aregiven in the other series, said ruler having two series of openingsthrough which are shown the numbers on the disc employed with said inchmarking and numbers comprising the results of said problems, each seriesof numbers on a disc being differently colored to insure theirpresentation through the proper openings.

In testimony whereof I have hereunto set my hand.

LOUIS M. RUDOLPH.

